摘要：针对大跨桥梁在地震作用下伸缩缝处的碰撞现象，以一座大跨三塔悬索桥为工程背景，建立了考虑墩柱弹塑性的空间非线性碰撞模型，采用非线性时程法详细分析了碰撞刚度、碰撞初始间隙等因素对碰撞效应的影响。分析结果表明：碰撞刚度在可能范围内取值，碰撞效应的变化不明显，碰撞刚度不是敏感参数；碰撞初始间隙是一个敏感参数，其大小对于碰撞效应有一定的影响，初始间隙比的变化对主引桥相对位移和引桥梁端位移影响比较明显。

Abstract: Based on the pounding phenomenon at expansion joints of long-span subjected to longitudinal earthquake and in combination with a realistic engineering project of a long-span multi-tower suspension bridge, the complex nonlinear model that considered the elasto-plastic behaviors of piers and the pound responses between the main span and the approach span was developed. The effects of some pounding parameters such as pounding-stiffness, initial gap at expansion joint were studied. The results indicate that the pounding stiffness is not essential parameter and its effect on pound responses is not obviously. But the initial gap at expansion joint has important effects on pounding effect such as the relative displacement between main span and approach span and the displacement of main girder.